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91.
Continuous wavelet analysis can be used to quantitatively describe local changes in cardiac rhythm oscillations. The following new indices of the wave structure of the cardiac rhythm were suggested: the rate of changes in the frequency of the oscillatory component within a given time interval, the lengths of the fading periods for specific frequency oscillations detected on the cardiointervalogram, and the changes in the instantaneous frequency-amplitude ratios during the observation period. These indices allow a deeper insight into sympathetic and parasympathetic oscillators that affect the cardiac rhythm. 相似文献
92.
V. G. Grigoryan A. R. Aghababyan A. N. Arakelyan A. Yu. Stepanyan 《Human physiology》2006,32(4):489-491
A comparative analysis of the time and amplitude characteristics of the negative N200 and positive P300 components of visual evoked potentials recorded at symmetric points of the frontal, parietal, temporal, and occipital areas of the right and left hemispheres of the cerebral cortex has been performed in subjects with or without the skill of operating a computer. Subjects inexperienced in an operator’s work exhibited an interhemispheric difference in the time and amplitude characteristics of the studied components. In subjects that had the skill of operating a computer, the interhemispheric difference was little, which suggests that the cortex plays only a small role in the cerebral control of this activity. 相似文献
93.
Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein
Hypersensitive C-reaction protein (hsCRP) may be a risk factor for cognitive impairment resulting from Alzheimer’s disease (AD), stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200) detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6), and homocysteine was estimated at 500m altitude, 3650m altitude, 3day, 1, and 3 month post arriving at the base camp (4400m), and 1 month after coming back to the 500m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400m). P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction. 相似文献
94.
Household‐level correlates of children's physical activity levels in and across 12 countries 下载免费PDF全文
Deirdre M. Harrington Fiona Gillison Stephanie T. Broyles Jean‐Philippe Chaput Mikael Fogelholm Gang Hu Rebecca Kuriyan Anura Kurpad Allana G. LeBlanc Carol Maher Jose Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Mark S. Tremblay Catrine Tudor‐Locke Pei Zhao Peter T. Katzmarzyk for the ISCOLE Research Group 《Obesity (Silver Spring, Md.)》2016,24(10):2150-2157
95.
96.
A. V. Naumenko G. N. Kovalev V. Yu. Naumenko E. I. Zaraisky N. S. Snegireva 《Biophysics》2006,51(2):209-214
The interactions of model proteins with porous matrices in biosensors are considered. The viscoelastic properties of casein and albumin were assessed by a dynamic method of a piezoquartz resonator by applying thin layers of the studied solutions to a piezocrystal. The experimental data on the viscoelastic characteristics of protein solutions of various concentrations were compared with the characteristics of their tangential motion in the porous carriers of cellulose nitrate. It was demonstrated that the parameters of dynamic viscosity correlated with the motion time of the protein solutions in the porous polymeric carrier. 相似文献
97.
98.
A. F. Pisarnitskii T. Yu. Rubeniya A. O. Rutitskii 《Applied Biochemistry and Microbiology》2006,42(5):514-518
Hemicellulose fractions were isolated from oak wood ethanol extracts (40–90%). To determine the composition of these fractions, they were hydrolyzed and the hydrolysis products in the form of trimethylsilyl derivatives were analyzed by GLC/MS. Depending on the content of the ethanol, hemicelluloses of a different composition were extracted from wood. In alcohols that were kept in oak wood, intended for manufacturing brandy and whisky, the content of the hemicelluloses increased depending on the duration of storage. It is assumed that this makes drinks more full-bodied and makes them softer. 相似文献
99.
100.
The urticating setae of Ochrogaster lunifer,an Australian processionary caterpillar of veterinary importance 下载免费PDF全文
L. E. PERKINS M. P. ZALUCKI N. R. PERKINS A. J. CAWDELL‐SMITH K. H. TODHUNTER W. L. BRYDEN B. W. CRIBB 《Medical and veterinary entomology》2016,30(2):241-245
The bag‐shelter moth, Ochrogaster lunifer Herrich‐Schaffer (Lepidoptera: Notodontidae), is associated with a condition called equine amnionitis and fetal loss (EAFL) on horse farms in Australia. Setal fragments from O. lunifer larvae have been identified in the placentas of experimentally aborted fetuses and their dams, and in clinical abortions. The gregarious larvae build silken nests in which large numbers cohabit over spring, summer and autumn. The final instars disperse to pupation sites in the ground where they overwinter. Field‐collected O. lunifer larvae, their nests and nearby soil were examined using light and electron microscopy to identify setae likely to cause EAFL and to determine where and how many were present. Microtrichia, barbed hairs and true setae were found on the exoskeletons of the larvae. True setae matching the majority of setal fragments described from equine tissue were found on third to eighth instar larvae or exuviae. The number of true setae increased with the age of the larva; eighth instars carried around 2.0–2.5 million true setae. The exuvia of the pre‐pupal instar was incorporated into the pupal chamber. The major sources of setae are likely to be nests, dispersing pre‐pupal larvae and their exuviae, and pupal chambers. 相似文献